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 ###Instrução: qual são todos os 1º viii abertos com u15 4º iv sendo gt
 ###Tabelas: CREATE TABLE key_terms (key_terms_id AUTO_INCREMENT PRIMARY KEY, English VARCHAR, Pali VARCHAR, Sanskrit VARCHAR, Chinese VARCHAR, Tibetan VARCHAR) CREATE TABLE winning_head_of_the_river_championship_events (winning_head_of_the_river_championship_events_id AUTO_INCREMENT PRIMARY KEY, Crew INT, Open 1st VIII VARCHAR, Open 2nd VIII VARCHAR, Open 3rd VIII VARCHAR, U16 1st VIII VARCHAR, U16 2nd VIII VARCHAR, U16 3rd VIII VARCHAR, U15 1st IV VARCHAR, U15 2nd IV VARCHAR, U15 3rd IV VARCHAR, U15 4th IV VARCHAR, U15 5th IV VARCHAR, U15 6th IV VARCHAR) CREATE TABLE former_special_cities_now_core_or_designated_cities (former_special_cities_now_core_or_designated_cities_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Japanese VARCHAR, Date of designation VARCHAR, Date of reclassification VARCHAR, Region VARCHAR, Prefecture VARCHAR) CREATE TABLE melodifestivalen_1999 (melodifestivalen_1999_id AUTO_INCREMENT PRIMARY KEY, Draw INT, Artist VARCHAR, Song VARCHAR, Points INT, Place VARCHAR) CREATE TABLE cardinal_numbers (cardinal_numbers_id AUTO_INCREMENT PRIMARY KEY, Number notation INT, Power notation VARCHAR, Short scale VARCHAR, Long scale VARCHAR, Indian (or South Asian) English VARCHAR)  
SELECT Open 1st VIII FROM winning_head_of_the_river_championship_events WHERE U15 4th IV = GT